1. Field of the Invention
The present invention relates generally to optical systems and, more specifically, to an apparatus for positioning optical components, such as those used in optical communications systems.
2. Background Information
With the increasing popularity of wide area networks (WANs), such as the Internet and/or the World Wide Web, network growth and traffic has exploded in recent years. Network users continue to demand faster networks and more access for both businesses and consumers. As network demands continue to increase, existing network infrastructures and technologies are reaching their limits.
An alternative to present day hardwired or fiber network solutions is the use of wireless optical communications. Wireless optical communications utilize point-to-point communications through free space and therefore do not require the routing of cables or fibers between locations. Thus, wireless optical communications are also known as free space or atmospheric optical communications. For instance, in a free space optical communication system, a beam of light is directed through free space from a transmitter at a first location to a receiver at a second location. Data or information is encoded into the beam of light, and therefore, the information is transmitted through free space from the inner location to the second location.
An important aspect of a free space optical communications system is tracking. In particular, it is important that the optical communications beam (e.g., laser beam) is aimed properly from the transmitter at the first location and that the receiver at the second location is aligned properly to receive the optical communications beam. For example, assume that a transmitter is mounted on a first building and that a receiver is mounted on a different second building. Assume further that there is a line of sight between the transmitter and receiver. It is important for the transmitter on the first building to be configured to accurately direct or aim the optical communications beam at the receiver on the second building.
One difficult aspect of utilizing free space optical communication systems is the initial alignment of the transmitter and receiver. In many instances, the transmitters and receivers will each comprise a single transceiver apparatus. In order to determine if the transceivers are properly aligned, it will generally be necessary to provide a feedback signal to each of the transceivers. However, if the feedback signal is to be provided via an optical path (which is typically the case), the transceivers must be at least partially aligned. This has been shown in practice to require a significant amount of time and resources.